PURPOSE: To prevent chipping of corners or ridges in advance caused unexpectedly in the handling of a process by providing a chamfered part by circular-arc forming or chamferring or the like to the corners or the ridges of a dielectric block.

CONSTITUTION: A circular-arc (round) 1a is formed to all ridges in a dielectric block 1. Plural resonator holes 2 are provided to the block 1 to form an inner conductor and an outer conductor is formed to an outer face of the block 1 thereby forming a block dielectric resonator 1. Then plural resonator holes 4 are provided to the block 3, an inner conductor is formed to the resonator hole 4, an outer conductor is formed to an outer face of the block 3 to form a block dielectric resonator 3. The chamferring process such as circular-arc forming or chamferring is conducted at the time of forming units such as dielectric blocks 1, 3 or in a post-process. Thus, chipping of corners or ridges caused unexpectedly in the handling of a process is prevented in advance.